Conditional sentences in English

Form

Conditionals are also called adverbial clauses.

We can divide such sentences into 5 groups.

The first group consists of adverbial clauses beginning with if = a neutral group or a neutral type followed by three basic types and a mixed group.

We divide them into these five types according to the sequences that they attract and in every group the conditional clauses can come before or after the main clause.
If it is a fine day tomorrow, we will go for a picnic / swimming / sailing.

There are two clauses in conditional sentences:
the 'if-clause' and the 'result clause'.
These clauses can be reversed.
We will go for a picnic tomorrow if it is a fine day.

The three basic types of combination can be said to express something that is:
1. probable (possible) : She will do it if you ask her.
2. improbable (impossible) She would do it if you asked her.
3. unfullfilled She would have done it if you had asked her.

The conditional sentence consists of two clauses: the conditional clause and the main clause.
The conditional clause starts with if or with if equivalents e.g:
(unless = if not, but for, provided, suppose, supposing, as long as, on condition that).

The conditional clause may come before or after the main clause, with no change in meaning.
When placed second, the conditional clause sounds less emphatic
If you do it, I'll give you an ice-cream.
I'll give you an ice-cream if you do it.
A comma is placed between the two clauses after the if clause.

There are three main types of conditional sentences:
1. Type 1. conditional clause + main clause
present tense + future (shall/will + infinitive) present tense + modal verb + infinitive,
If I get some fruit, I'll make you a cake.
If I get some fruit, I can make you a cake.
If I get some fruit, will you make me a cake? (= a request)

2. Type 2. conditional clause + main clause
past tense + should/would + infinitive / past form of modal verb + infinitive,
If I got some fruit, I would/should, could, might etc. make you a cake.
If I got some fruit, would you make a cake? (= a request)

3. Type 3. conditional clause main clause
past perfect tense + should/would etc. + perfect infinitive
If I had got some fruit, I would have made you a cake.

Exercises

Exercises - Conditional sentences